1. Field of the Invention
The present invention relates to a video and audio processing device including a specific-standard digital input terminal, an analog video input terminal, a specific-standard digital output terminal, and an analog video output terminal.
2. Description of the Related Art
An AV amplifier includes an HDMI output terminal and an analog video output terminal (component, S-video, CVBS, or the like) as a video output terminal. However, the AV amplifier can output video data from only either the HDMI output terminal or the analog video output terminal through an image processing unit (hereinafter referred to as VSP). Therefore, it is necessary that a video output destination be set to one of the HDMI output terminal and the analog video output terminal by a user manipulation. When the setting is mistakenly performed, the video cannot be output to a display device through the VSP. For example, while the display devices are connected to the HDMI output terminal and the analog video output terminal, the display device connected to the HDMI output terminal is put into a power-off state, and the display device connected to the analog video output terminal is put into a power-on state to display the video on the display device. In such cases, it is necessary that the video output destination be set to the analog video output terminal by the user manipulation.
In order to solve the problem, it is considered that the video output destination is automatically set. For example, a hot plug signal is detected from the display device connected to the HDMI output terminal, the video output destination is set to the HDMI output terminal when the hot plug signal is at a high level, and the video output destination is set to the analog video output terminal when the hot plug signal is at a low level.
In this case, HDMI is specific-standard digital data including video data and audio data. The AV amplifier is permitted to output the HDMI data only to a device in which HDCP authentication is successfully performed. When the video output destination is set to the analog video output terminal, the AV amplifier does not successfully perform the HDCP authentication of the display device connected to the analog video output terminal. Accordingly, the AV amplifier cannot set the video input source to the HDMI input terminal. That is, the AV amplifier sets the video input source to the analog video input terminal, and the AV amplifier outputs the video signal, fed from the analog video input terminal, from the analog video output terminal. Therefore, the AV amplifier also sets the audio input source to the analog audio input terminal or the digital audio input terminal, and the AV amplifier amplifies the audio signal, fed from the analog audio input terminal or the digital audio input terminal, to output the amplified audio signal to a speaker. As a result, the AV amplifier cannot amplify the audio data, included in the HDMI data, to output the audio data to the speaker.